Photo: Amazon MGM Studios/Everett Collection Hugh Jackman takes top billing in The Sheep Detectives as murder victim George Hardy, but the movie’s real leads are its animal characters, which are all members of George’s flock of artfully computer-generated sheep. There’s Sebastian (Bryan Cranston), a brooding Icelandic ram who keeps to himself, and Cloud (Regina Hall), a fluffy Cheviot known for her looks. Sir Ritchfield (Patrick Stewart) is a doughty elder Boreray with majestic horns, but